Ziziphus Tourn. ex Miller

Shrubs or trees, rarely decumbent or creeping; branches often zig-zag. Leaves alternate or opposite, entire or crenate, coiraceous, 3-5-nerved from the base, petiolate; stipules either single or rarely two, spinescent; spines sharp, curved or straight, recurved ones shorter. Inflorescence axillary or terminal cymes or thyrses. Flowers pentamerous, bisexual or polygamous, perigynous, pedicellate. Petals cucullate, incurved or deflexed, rarely absent. Stamens included or excluded, inserted below the disc. Disc flat or pitted, 5 or 10-lobed, or rarely entire, often with 10 depressions covering the receptacle, margins free. Ovary immersed in the disc and adnate to its base, 2-4-loculed; style 2-4, free, diverging or combined; stigma papillose. Drupes globose or oblong; putaman woody or horny, 1-3-celled. Seeds 1-3, plano-convex, testa thin, brittle, smooth shining, exalbuminous or with scanty endosperm; cotyledons thick; radicle short.

Temperate and tropical parts of the world, chiefly in Asia and America, a few extending to the Pacific Islands and Australia; ca 135 species, 17 in India.

Literature. KHOSHOO T.N. & N. SINGH (1963) Cytology of North-west Indian trees I. Ziziphus jujuba and Z. rotundifolia. Silvae Genetica 12, 5: 158-165.

KEY TO THE SPECIES

1a. Cymes axillary, sessile or shortly pedunculate

2

b. Cymes terminal or flowers in lateral panicles, distinctly pedunculate

16

2a. Flowers in sessile cymes or cymose fascicles

3

b. Flowers in pedunculate cymes

10

3a. Leaves glabrous beneath; disc not pitted

4

b. Leaves tomentose beneath; disc pitted

6

4a. Branchlets fasciculate

9. Ziziphus jujuba

b. Branchlets not fasciculate

5

5a. Leaves elliptic, obtuse; basal nerves prominent beneath and continued to the apex

6. Ziziphus glabrata

b. Leaves ovate, not obtuse; basal nerves not prominent beneath and not continued to the apex

13. Ziziphus oxyphylla

6a. Leaves obliquely ovate, entire or minutely denticulate, base oblique

7

b. Leaves not obliquely ovate, serrulate, base rounded

8

7a. Transverse nerves at right angle to mid-rib

3. Ziziphus brunoniana

b. Transverse nerves not at right angle to mid-rib

12. Ziziphus oenoplia

8a. Leaves truncate at apex

15. Ziziphus truncata

b. Leaves not truncate at apex

9

9a. Leaves fuscus tomentose beneath

10. Ziziphus mauritiana

b. Leaves grey tomentose beneath

11. Ziziphus nummularia

10a. Style 3-cleft, distinct or nearly so

11

b. Style 2-cleft, connate up to the middle

13

11a. Leaves and fruits tomentose

17. Ziziphus xylopyra

b. Leaves glabrous, except on nerves beneath; fruits glabrous

12

12a. Plants armed with thorns

7. Ziziphus horrida

b. Plants unarmed

4. Ziziphus caracutta

13a. Ovary villous

14

b. Ovary glabrous

15

14a Leaves acuminate; petals absent; fruits obovoid, pointed at apex

2. Ziziphus apetala

b. Leaves obtusely caudate-acuminate; petals present; fruits globose, not pointed at apex

1. Ziziphus andamanica

15a. Leaves more than 5 cm long, lateral nerves continous to the apex; petioles up to 7 mm long

8. Ziziphus incurva

b. Leaves less than 5 cm long, lateral nerves end near the apex; petioles more than 7 mm long

16. Ziziphus williamii

16a. Petals absent; primary nerves branched

14. Ziziphus rugosa

b. Petals present; primary nerves unbranched

5. Ziziphus funiculosa

List of Lower Taxa